Heat exchanger

ABSTRACT

Heat exchanger comprising circulation elements fluidically connected to one or more manifolds which are configured to feed a heat-carrier fluid in the circulation elements and to collect the heat-carrier fluid at exit from the circulation elements.

FIELD OF THE INVENTION

Embodiments described here concern a heat exchanger. In particular, aheat exchanger described in the present invention is suitable to promotethe heat exchange between two fluids, of which at least one is aheat-carrier fluid which recirculates in the heat exchanger thanks tosuitable feed means.

BACKGROUND OF THE INVENTION

Heat exchangers are known which comprise a plurality of circulationelements able to be passed through by fluids, such as for examplecooling fluids.

These circulation elements usually comprise pipes or channels and havean oblong development. The pipes or channels are disposed parallel toeach other and distributed over the width of the circulation element.

In particular, some circulation elements comprise a plurality of oblongpipes disposed parallel. Other circulation elements, on the other hand,appear as an oblong body with a flattened cross section inside which aplurality of parallel channels are made.

Furthermore, the circulation elements are located parallel to eachother, and heat exchange fins can be attached between adjacentcirculation elements.

In particular, the fins are attached on the external surfaces of thecirculation elements to increase the useful heat exchange surface of thecirculation elements.

The circulation elements are in turn connected, at their respectiveopposite ends, to manifolds, configured to be passed through by theheat-carrier fluid, which has to enter the circulation elements, orwhich has just come out of them.

The manifolds are therefore connected to at least one feed duct and arecovery duct respectively to introduce the heat-carrier fluid towardthe heat exchanger, and recover it from the latter.

The manifolds, in turn, can be connected to a circuit, for example acooling circuit, in which the same heat-carrier fluid is subjected topredefined thermodynamic cycles.

The circuit generally comprises a mean to feed the heat-carrier fluidwhich can be configured, for example, as a compressor or as a pump.

The mean to feed the heat-carrier fluid can modulate the parameters ofthe feed of the fluid (for example pressure or flow rate) based on theperformances required of the heat exchanger.

This modulation can generate pressure waves in the heat-carrier fluidwhich can be transmitted in it with a certain frequency. The amplitudeand frequency of the pressure waves may depend on the feed parameters(pressure and flow rate) and on the type of feed mean.

Heat exchangers of the known type as described above have somedisadvantages.

A first disadvantage of known solutions is that vibrations of the heatexchanger can be generated, excited by possible resonances between theflow of the heat-carrier fluid and the structure of the exchangeritself. In fact, some amplitude and frequency values of the pressurewaves as above may be such as to trigger a resonance with the vibrationfrequencies that are characteristic of the geometry of the heatexchanger or parts of it.

These vibrations may be transient and appear only during the modulationof the feed parameters, or they may be stationary and occur even whenthe feed parameters of the heat-carrier fluid are constant over time.

Another disadvantage is that this resonance between the feed mean andthe structure of the exchanger can lead to a deterioration in theperformance of the exchanger, interfering with the thermo-fluid dynamicsof the entire apparatus.

This deterioration in performance can also lead to an energyinefficiency of the exchanger itself, which can cause an increase inpolluting emissions linked to the functioning of the exchanger.

Another disadvantage is that this resonance between the feed mean andthe structure of the exchanger can lead to the generation of noiseswhich, in some cases, can be particularly annoying.

Another disadvantage is that the vibrations can lead to the breakage ofcomponents of the exchanger, causing a worsening of its performance.

Another disadvantage is that the vibrations can also be transmitted toother parts of the hydraulic circuit associated with the exchanger,causing malfunctions, inefficiency and in some cases breakages.

To try to overcome some of these disadvantages, some solutions known inthe state of the art have been developed, which provide structuralreinforcement elements to be disposed in the manifolds. Solutions ofthis type are known, for example, from prior art documents JP2008/298349 A, US 2019/162488 A1 and JP S53 63771 U.

Some of these solutions, such as US 2019/162488 A1 and JP 55363771 U forexample, provide to distribute the structural reinforcement elementshomogeneously along the entire length of the manifold in order to definea suitable structural reinforcement for the latter.

Another solution, described by JP 2008/298349 A, provides to dispose aplate in the manifold, provided with a hole or an equivalent recess onone of the perimeter sides of the plate, which allows the passage of thefluid. The plate is located in a median position of symmetry of themanifold, which is important since it allows the plate to perform thefunction of a stiffening mean. In fact, in order to lighten as much aspossible the weight of the exchanger described in this document, thewalls of its structural components have reduced thicknesses and thismeans that the exchanger can be subject to resonance phenomena,generated by the mechanical lightening of the structure, with consequentvibrations that can cause damage to some components of the structureitself.

There is therefore a need to perfect a heat exchanger which can overcomeat least one of the disadvantages of the state of the art.

In particular, one purpose of the present invention is to provide a heatexchanger that can at least limit, or even eliminate, the excitation ofvibrations due to the resonance between the feed of the heat-carrierfluid and the structure of the exchanger itself.

Another purpose is to provide a heat exchanger that can reduce the noisepollution produced by said vibrations.

Another purpose of the present invention is to provide a heat exchangerthat reduces the breakages due to the resonance phenomena between thefeed of the heat-carrier fluid and the structure of the exchanger.

Yet another purpose of the present invention is to reduce or eliminatethe transmission of said vibrations to other components of the circuitassociated with the exchanger.

Another purpose is to perfect a heat exchanger which limits orcompletely prevents the worsening of its thermo-fluid dynamicperformance due to vibrations.

Another purpose is to provide an exchanger which is more efficient froman energy point of view, less polluting, and more durable over time.

The Applicant has devised, tested and embodied the present invention toovercome the shortcomings of the state of the art and to obtain theseand other purposes and advantages.

SUMMARY OF THE INVENTION

The present invention is set forth and characterized in the independentclaim. The dependent claims describe other characteristics of thepresent invention or variants to the main inventive idea.

In accordance with the above purposes, a heat exchanger is describedthat overcomes the limits of the state of the art and eliminates thedefects present therein.

In accordance with some embodiments, a heat exchanger is providedcomprising at least one heat exchange unit and recirculation meansfluidically connected to the unit.

The heat exchange unit comprises circulation elements which can be, forexample but not limited to, of the type with “micro-channels”.

In some embodiments, the recirculation means comprise at least onetubular manifold with a cross section for the passage of a heat-carrierfluid.

The manifold is closed at its opposite ends by respective end caps andis fluidically connected to the circulation elements of the heatexchange unit, being configured to feed a heat-carrier fluid into thecirculation elements and to collect the heat-carrier fluid at exittherefrom.

According to one aspect, the heat exchanger comprises clamping meansoperatively associated with at least one of the manifolds.

In some embodiments, the damping means are configured to dampen pressurewaves that characterize the flow of heat-carrier fluid, and modify theirrelative frequency and/or amplitude in order to prevent the occurrenceof resonance phenomena.

According to one aspect of the present invention, the damping means aredisposed in the proximity of one of the end caps.

This position of the damping means is advantageous since it allows toachieve the effect of clamping the pressure waves, with the consequentmodification of the relative frequency and/or amplitude of such waves,without significantly impacting the fluid-dynamic efficiency of the heatexchanger.

In some embodiments, the damping means comprise at least one distributorbaffle disposed transversely inside the at least one manifold.

The distributor baffle can have a plan shape defined by an externalperimeter and at least partly mating with the passage cross section ofthe manifold.

According to some embodiments, the distributor baffle comprises one ormore through holes.

The through holes can have a cross section that varies as a function ofthe thickness of the distributor baffle.

According to other embodiments, the perimeter of the plan shape of thedistributor baffle can partly differ from the passage cross section ofthe manifold in which it is disposed. In this way, the distributorbaffle can define, in cooperation with the manifold, one or more passagegaps for the flow of the heat-carrier fluid.

According to other embodiments, the damping means can comprise a phaseshifter unit fluidically connected to the recirculation means.

The phase shifter unit can comprise at least one phase shift chamber andat least one pipe configured to fluidically connect the phase shiftchamber with a manifold.

The present invention also concerns an exchanger comprising a pluralityof distributor baffles, even different from each other, and a pluralityof phase shifter units both operatively associated with one or moremanifolds.

In some embodiments, at least one manifold can be fluidically connectedto a feed pipe for feeding a heat-carrier fluid. Furthermore, at leastone manifold can be fluidically connected to a recovery pipe.

The clamping means as described here can be advantageously integrated inheat exchangers even in a step that follows their production.

BRIEF DESCRIPTION OF THE DRAWINGS

These and other aspects, characteristics and advantages of the presentinvention will become apparent from the following description of someembodiments, given as a non-restrictive example with reference to theattached drawings wherein:

FIGS. 1 and 2 are schematic representations of longitudinal sections oftwo different embodiments of an exchanger according to the presentinvention;

FIG. 3 is a partial and schematic three-dimensional representation ofanother embodiment of a heat exchanger according to the presentinvention, in which some parts have been removed;

FIGS. 4, 5 and 6 are partial and schematic representations of crosssections of as many possible embodiments of a distributor bafflecomprised in the heat exchanger according to the present invention;

FIGS. 7 to 10 are partial and schematic representations of longitudinalsections that show as many possible embodiments of clamping meanscomprised in the heat exchanger according to the present invention.

To facilitate comprehension, the same reference numbers have been used,where possible, to identify identical common elements in the drawings.It is understood that elements and characteristics of one embodiment canconveniently be combined or incorporated into other embodiments withoutfurther clarifications.

DETAILED DESCRIPTION OF SOME EMBODIMENTS

We will now refer in detail to the possible embodiments of theinvention, of which one or more examples are shown in the attacheddrawings, by way of a non-limiting illustration. The phraseology andterminology used here are also for the purposes of providingnon-limiting examples.

With reference to the attached drawings, the present invention concernsa heat exchanger, indicated as a whole with reference number 10.

The heat exchanger 10 comprises at least one heat exchange unit 11,hereafter unit 11, and recirculation means 12 fluidically connected tothe unit 11. The unit 11 can comprise a plurality of circulationelements 13 having an oblong development along a longitudinal axis Z anddistanced from each other.

The circulation elements 13 can be placed on planes P parallel to eachother and disposed in succession along a positioning axis Xperpendicular to the planes P (FIG. 3 ), preferably equidistant fromeach other along the positioning axis X.

According to some embodiments, not shown, the circulation elements 13can comprise a plurality of different tubes distanced from each other inparallel along a transverse axis that defines the width of thecirculation elements 13. The diameter of the tubes can be a fewcentimeters.

In other possible embodiments, the circulation elements 13 can beconfigured as substantially flat elements each incorporating a pluralityof channels 14 in a single body (FIG. 3 ).

The channels 14 extend between a first end 15 and a second end 16 of thecirculation element 13.

Each channel 14 has a very small cross section for the passage of thefluid, for example comprised between 5*10⁻⁵ and 20 square millimeters.For this reason, the channels in question are also called“micro-channels” and consequently, by extension, we speak of a“micro-channel” unit 11.

In some embodiments, the channels 14 can be distanced from each other inparallel along a transverse axis Y (FIG. 3 ) which defines the directionof the width of the circulation elements 13.

The channels 14 can have a shape of the cross section for the passage ofthe fluid that is rectangular, circular, semicircular, although othergeometric shapes are not excluded.

The circulation elements 13 can have a shape of the cross section thatis substantially flat, that is, in which the width is greater than thethickness, for example at least 5 times greater than the thickness.

The circulation elements 13 can be made of a thermally conductivematerial, such as a metal material, for example selected from a groupcomprising aluminum or its alloys, stainless steel, or copper. Thechoice of these materials also allows to give the elements 13 adequateresistance to corrosion.

In some embodiments, the circulation elements 13 can be provided with afirst surface 17 and a second surface 18 at least one of which, usuallyboth, is in direct contact with a plurality of fins 19.

Each circulation element 13 can be disposed so that its first surface 17faces the second surface 18 of the adjacent circulation element 13.

The circulation elements 13 can be distanced from each other by theplurality of fins 19 which can be integrally attached to the circulationelements 13, for example by welding, more specifically by brazing.

The fins 19 are disposed along the oblong development of two adjacentcirculation elements 13, as shown in FIGS. 1-3 , and can be defined byat least one substantially flat and rectangular sheet.

The plurality of fins 19 can be obtained from a sheet, suitablycorrugated or bent in a zig zag manner according to a homogeneousdevelopment in order to define the heat exchange surfaces.

In other words, each fin 19 is defined by each of the bent segments of asheet.

The fins 19 can be disposed adjacent to each other and transverse withrespect to the axis Z of longitudinal development of the circulationelements 13.

According to some embodiments, the recirculation means 12 can befluidically connected to each circulation element 13 in order tocirculate a heat-carrier fluid.

With the term circulation we mean both the feed and also the collectionof the heat-carrier fluid in the circulation elements 13.

In this way, it can be provided that the recirculation means 12 allowthe circulation of the heat-carrier fluid in the circulation elements13.

The recirculation means 12 can be associated with the first end 15 andwith the second end 16 of each circulation element 13 and can compriseat least one or more tubular manifolds 20 fluidically connected to thecirculation elements 13 (FIG. 3 ).

According to some embodiments, the manifolds 20 a, 20 b can beconfigured as tubular-shaped bodies delimited by walls 29 which developparallel to the positioning axis X, and which have a cross section forthe passage of a heat-carrier fluid.

Each manifold 20 a, 20 b can be closed, or “capped”, at the ends bymeans of end caps 28 a, 28 b, by means of welding, preferably brazing.

The caps 28 a, 28 b, or “end caps”, can be configured as plates having aplan shape substantially similar to the passage cross section of themanifold 20.

In some embodiments, the passage cross section of the manifold 20 iscircular. In other embodiments, the passage section is in the shape of a“D”. However, other shapes for the passage cross section of the manifold20 are not excluded.

According to some embodiments, a heat exchanger 10 according to thepresent invention can comprise a first manifold 20 a and a secondmanifold 20 b, both associated respectively with the first end 15 andwith the second end 16 of the circulation elements 13, or vice versa.

In some embodiments, the recirculation means 12 comprise at least onefeed pipe 40 and at least one recovery pipe 41.

The feed pipe 40 can be fluidically associated with a manifold 20.

The feed pipe 40 allows to put the recirculation means 12 in fluidiccommunication with a feed circuit 22 which, in some embodiments, cancomprise a feed mean 23 disposed upstream of the feed pipe 40.

The feed mean 23 can be any known device whatsoever suitable to generatea flow of heat-carrier fluid. For example, the feed mean 23 can be acompressor or a pump.

The recovery pipe 41 can be fluidically connected to a manifold 20 andcan be configured to collect the heat-carrier fluid at exit from thecirculation elements 13.

The recovery pipe 41 can in turn be put in fluidic communication withthe feed circuit 22, upstream of the feed mean 23.

In some embodiments, the feed pipe 40 can be associated with the firstmanifold 20 a and the recovery pipe 41 can be associated with the secondmanifold 20 b, or vice versa.

Referring to FIGS. 1 and 2 , both the feed pipe 40 and also the recoverypipe 41 can be fluidically connected to a manifold 20. In particular, inthese embodiments the manifold 20 a can also comprise a dividing baffle24, interposed between the inlet of the feed pipe 40 and the inlet ofthe recovery pipe 41. More in particular, the dividing baffle 24 definestwo fluidically separated portions in the manifold 20 a. A planecontaining the dividing baffle 24 and parallel to the axes Y and Z canbe called the flow inversion plane A (FIG. 3 ).

Note that FIGS. 9 and 10 show embodiments of the heat exchanger 10without the dividing baffle 24. In fact, in the above embodiments therecovery pipe 41 can be associated with another manifold 20 b, notshown.

According to one aspect of the invention, the heat exchanger 10 cancomprise clamping means 21 which can be operatively associated with themanifolds 20 in order to clamp pressure waves that characterize the flowof heat-carrier fluid.

In this case, the damping means 21 are configured to constitute adiscontinuity with respect to the geometry of the manifold 20 with whichthey are associated, preventing the excitation of vibrations due to theresonance between the flow of heat-carrier fluid and the structure ofthe entire heat exchanger 10. In fact, the damping means 21 can modifythe frequency and/or the amplitude of the pressure waves that passthrough the heat-carrier fluid.

Another advantage of the present invention consists in the fact that thedamping means 21 as described here can be easily integrated into heatexchangers even in a step that follows their production.

In some embodiments, the damping means 21 comprise at least onedistributor baffle 25 (FIGS. 1, 2 and 3 ) which, in some embodiments,can be disposed transversely with respect to the longitudinaldevelopment of the manifold 20, that is, transversely with respect tothe positioning axis X.

Furthermore, the distributor baffle 25 can be configured as a flat bodywith a thickness S and a plan shape at least partly mating with thepassage cross section of at least one of the manifolds 20 (FIGS. 4, 5and 6 ). Preferably, the external perimeter 25 a of the distributorbaffle 25 is exactly mating with the shape of the cross section of themanifold 20 in which the baffle is installed.

According to some embodiments, the distributor baffle 25 can compriseone or more through distribution holes 26 that pass through it.

The distribution holes 26 can be of any shape whatsoever and their crosssection can be variable as a function of the thickness S of thedistributor baffle 25 (FIGS. 1 and 2 ), that is, variable along thepositioning axis X.

As shown in FIGS. 1 and 2 , in some embodiments the distribution holes26 can have a conical development as a function of the thickness S. Inother embodiments, the distribution holes 26 can have a developmentalong the axis X which provides a narrowing of the section of the hole26 followed by a widening of the section.

A distributor baffle can also comprise a plurality of differentdistribution holes 26 (FIG. 6 ).

According to other embodiments, the plan shape of the distributor baffle25 can partly differ from the passage cross section of the baffle 20with which it is associated.

In this way, the distributor baffle 25, in cooperation with the manifold20, can define one or more passage gaps 27 for the flow of heat-carrierfluid (FIGS. 4, 5 and 6 ), through which the latter can flow in additionor as an alternative to the distribution holes 26.

The distribution holes 26 and/or the passage gaps 27 are configured toallow the heat-carrier fluid flowing in the manifold 20 to pass from oneside to the other of the distributor baffle 25.

In other embodiments, the heat exchanger 10 can comprise a plurality ofdistributor baffles 25, possibly disposed in different positions insidethe one or more manifolds 20. The distributor baffles 25 can also bedifferent from each other, that is, they can comprise distribution holes26 and/or define passage gaps 27 that differ from one distributor baffle25 to another.

A person of skill in the art can easily understand that the shape andamount of distribution holes 26 and/or the passage gaps 27 can bedesigned and sized as a function of the overall geometry of the entireheat exchanger 10 and of the thermo-fluid dynamic characteristics of theflow of heat-carrier fluid which, during use, will flow inside it.

In preferred embodiments, a distributor baffle 25 can be disposed in amanifold 20 in the proximity of one of the end caps 28 a, 28 b.

In particular, in some embodiments, at least one circulation element 13is disposed between at least one of the end caps 28 a, 28 b and adistributor baffle 25. More preferably, only one circulation element 13is disposed between at least one of the end caps 28 a, 28 b and thedistributor baffle 25.

As shown in FIGS. 1 and 2 , the passage cross section of the manifold 20is substantially free of clamping means for most of its longitudinalextension, a distributor baffle 25 being provided only in the proximityof the end cap 28 a. The absence of distributor baffles 25 in otherpositions improves the circulation of the heat-carrier fluid and theheat exchange efficiency of the heat exchanger 10. This is advantageous,especially if one considers that the solutions known in the state of theart need to dispose such distributor baffles either in a median zone ofthe manifold equidistant from its opposite ends or along the entiremanifold, in order to guarantee the necessary structural reinforcementaction of the manifold itself.

According to another aspect of the invention, the damping means 21 cancomprise a phase shifter unit 30 fluidically connected to a manifold 20.

In some embodiments, the phase shifter unit 30 can comprise a phaseshift chamber 31 which can be configured as a tubular body generallydefined by a cross section and a longitudinal development.

The phase shift chamber 31 can be configured to receive at least part ofthe flow of heat-carrier fluid which flows in the manifold 20 with whichit is associated.

According to some embodiments, a phase shift chamber 31 can befluidically connected to at least one of the manifolds 20 a, 20 b bymeans of a single pipe 32 (FIG. 1 ) through which the fluid enters andexits the phase shift chamber 31.

In other embodiments, a phase shift chamber 31 can be fluidicallyconnected to at least one of the manifolds 20 a, 20 b by means of afirst pipe 33 and a second pipe 34 (FIG. 2 ), which respectively leadthe fluid into the phase shift chamber 31 and evacuate the fluidtherefrom.

A person of skill in the art can easily understand that the sizing anddesign of the phase shift chamber 31, specifically the definition of thecross section and its longitudinal development, depend on the geometryof the entire heat exchanger 10 and on the thermo-fluid dynamiccharacteristics of the flow of heat-carrier fluid which, during use,will flow inside it.

According to some embodiments, one of either the first pipe 33 or thesecond pipe 34 can be connected to one of the manifolds 20, 20 b abovethe flow inversion plane A, and the other pipe can be connected to thesame manifold below of the flow inversion plane A.

In some embodiments, a heat exchanger 10 can comprise one or moredistributor baffles 25 comprised in the manifolds 20 a, 20 b and atleast one phase shift chamber 31 fluidically connected to one of themanifolds 20 a, 20 b by means of a single pipe 32 (FIG. 1 ).

In other embodiments, a heat exchanger 10 can comprise one or moredistributor baffles 25 comprised in the manifolds 20 a, 20 b and atleast one phase shift chamber 31 fluidically connected to one of themanifolds 20 a, 20 b by means of a first pipe 33 and a second pipe 34(FIG. 2 ).

In other embodiments, not shown, a heat exchanger 10 can comprise aphase shift chamber 31 fluidically connected to one of the manifolds 20a, 20 b by means of one or more pipes and be without distributor baffles25. In these embodiments, the phase shift function is performedexclusively by the phase shift chamber 31.

According to other embodiments, a heat exchanger 10 can comprise one ormore distributor baffles 25 comprised in the manifolds 20 and aplurality of phase shift chambers 31 fluidically connected to at leastone manifold 20.

A person of skill in the art will easily understand that the dispositionand number of the distributor baffles 25 and of the phase shift chambers31 depend on the geometric characteristics of the entire heat exchanger10 and on the thermo-fluid dynamic characteristics of the flow ofheat-carrier fluid flowing through it.

In other possible variants, the damping means 21 can comprise one ormore protrusions 50, 53, 54 (FIGS. 7 and 8 ).

In some embodiments, the protrusions 50 can be associated with at leastone of the end caps 28 a, 28 b of a manifold 20 and can project towardthe inside of the manifold 20 itself (FIG. 7 ), or be associated withthe walls 29 of the manifold 20.

In other embodiments, the protrusions 53, 54 can be associated with adividing baffle 24 of a heat exchanger 10 (FIG. 8 ) or with the walls 29of the manifold 20.

The protrusions 50, 53, 54 can be, for example but not limited to, of aconical shape, of a hemispherical shape, of a truncated conical orpyramidal shape. However, we do not exclude other shapes that can allowthe protrusions 50, 53, 54 to attenuate the vibrations transmitted inthe heat-carrier fluid. Furthermore, it is not excluded that theprotrusions 50, 53, 54 can be associated with a distributor baffle 25and/or with a phase shifter unit 30.

In other embodiments, the damping means 21 can comprise elongatedprotrusions 51, 56 which have an oblong development (FIGS. 7 and 9 ).The elongated protrusions 51, 56 can develop inside a manifold 20 of theheat exchanger 10.

In some embodiments, the elongated protrusions 51, 56 can be associatedwith at least one of the end caps 28 a, 28 b of a manifold 20 and canprotrude toward the inside of the manifold 20 itself (FIG. 9 ).

In other embodiments, the elongated protrusions 51, 56 can be associatedwith a dividing baffle 24 of a heat exchanger 10 (FIG. 7 ) or with thewalls 29 of the manifold 20.

The elongated protrusions 51, 56 can be substantially cylindrical inshape, but also have a truncated cone, conical or pyramidal shape.However, we do not exclude other shapes that can allow the elongatedprotrusions 51, 56 to attenuate the vibrations transmitted in theheat-carrier fluid. Furthermore, it is not excluded that the elongatedprotrusions 51, 56 can be associated with a distributor baffle 25 and/orwith a phase shifter unit 30, such as those described above.

In some embodiments, the external surface of the protrusions 50, 53, 54and/or of the elongated protrusions 51, 56 can be corrugated.

In possible variants, the damping means 21 can comprise one or moretubular elements 52 (FIG. 8 ).

According to some embodiments, a tubular element 52 can be associatedwith at least one of the end caps 28 a, 28 b.

In other embodiments, a tubular element 52 can be associated with adividing baffle 24 of a heat exchanger 10 or with the walls 29 of themanifold 20.

In other embodiments, not shown, a tubular element 52 can be associatedwith a distributor baffle 25 and/or with a phase shifter unit 30.

The tubular element 52 can have a circular or oval section. However,other types of section are not excluded such as, for example, but notlimited to, a square, rectangular or polygonal section and others.

In some embodiments, the tubular element 52 can be perforated laterally.

The presence of a plurality of tubular elements 52, possibly operativelyinterconnected, for example disposed concentric with each other, is notexcluded.

According to other variants, the damping means 21 can comprise mobileclamper elements 55, as in the example shown in FIG. 9 .

According to some embodiments, a mobile clamper element 55 can beassociated with at least one of the end caps 28 a, 28 b.

In other embodiments, not shown, the mobile damper element 55 can beassociated with a dividing baffle 24 of a heat exchanger 10, or with thewalls 29 of the manifold 20.

In other embodiments, not shown, the mobile damper element 55 can beassociated with a distributor baffle 25 and/or with a phase shifter unit30, such as those described above.

In some embodiments, a mobile damper element 55 can comprise a bodyoperatively associated with the manifold 20 by means of elastic means.The body can capture the pressure pulsations transmitted in theheat-carrier fluid and transmit them to the elastic means configured toabsorb the pulsations.

According to other possible variants, the damping means 21 can comprisetransverse protrusions 57, 58, 59 which protrude into a manifold 20 in adirection substantially transverse with respect to the longitudinaldevelopment thereof (FIG. 10 ).

In some embodiments, the transverse protrusions can be configured as asingle protrusion or as a series of successive protrusions. Furthermore,in some embodiments, the transverse protrusions 58 can be made in such away as to at least partly follow the perimeter development of thesection of the manifold 20.

In other embodiments, the damping means 21 can comprise an insert 60associated with a manifold 20.

In some embodiments, the insert 60 can constitute a structuraldiscontinuity in the manifold 20.

According to some embodiments, the insert 60 can be configured as aportion of the manifold 20 made of a different material than that withwhich the manifold 20 is made, and which develops in continuity with thewalls 29.

In some embodiments, an insert 60 can be made of plastic, polymer,elastoplastic, metal, ceramic material, of rubber or synthetic ornatural fibers.

According to other embodiments, the insert 60 can be configured as aportion of the manifold 20 in which there is provided a geometricvariation thereof. According to a non-limiting example, the insert 60can have an annular shape and can have a different thickness, greater orlesser, than the thickness of the walls 29 of a manifold 20.

In other embodiments, the damping means can comprise free or semi-freebodies 61, for example retained by a cable, contained in a manifold 20of a heat exchanger.

The bodies 61 can be of a shape and/or of materials such as to allow areduction of the vibrations that are transmitted in the heat-carrierfluid in which they are immersed.

In accordance with other possible variants, the damping means 21 can beconfigured as protruding portions 62 a, 62 b of the feed pipe 40 and/orof the recovery pipe 41 and/or of the circulation elements 13,configured to protrude inside a manifold 20 so as to constitute adiscontinuity in the geometry thereof.

According to some embodiments, one or more holes can be made in theprotruding portions 62 a, 62 b.

In other embodiments, the damping means 21 comprise at least onemembrane 63 operatively associated with a manifold 20 (FIG. 8 ). Themembrane 63 can be flexible and can be configured to absorb vibrationsthat are transmitted in the heat-carrier fluid.

In some embodiments, the membrane 63 can be of plastic or polymermaterial, of fabric, non-woven fabric, rubber and suchlike.

The membrane 63 can be perforated and/or micro-perforated.

It is noted that all the embodiments of damping means 21 described areconfigured to constitute a geometric discontinuity in the manifold 20 soas to reduce the propagation of pulsations in the heat-carrier fluidcirculating in the manifold 20. Therefore, modifications to theembodiments described and/or their combinations are not excluded.

It is clear that modifications and/or additions of parts may be made tothe heat exchanger 10 as described heretofore, without departing fromthe field and scope of the present invention as defined by the claims.

In the following claims, the sole purpose of the references in bracketsis to facilitate reading: they must not be considered as restrictivefactors with regard to the field of protection claimed in the specificclaims.

1. Heat exchanger comprising circulation elements fluidically connectedto one or more manifolds which are closed at the ends by respective endcaps and are configured to feed a heat-carrier fluid in said circulationelements and to collect said heat-carrier fluid at exit from saidcirculation elements, damping means operatively associated with at leastone of said manifolds able to damp pressure waves which characterize theflow of heat-carrier fluid and modify their relative frequency and/oramplitude in order to prevent the occurrence of resonance phenomena,wherein said damping means are disposed in the proximity of one of saidend caps.
 2. Heat exchanger as in claim 1, wherein said manifolds have apassage cross section for said heat-carrier fluid, said damping meanscomprise at least one distributor baffle disposed transversely inside atleast one manifold, said distributor baffle having a plan shape definedby an external perimeter and at least partly mating with said passagecross section of said manifold.
 3. Heat exchanger as in claim 2, whereinsaid distributor baffle has a perimeter edge having a plan shape whichpartly differs from said passage cross section of said at least onemanifold in which it is disposed, so as to define, in cooperation withsaid manifold, one or more passage gaps.
 4. Heat exchanger as in claim2, wherein said distributor baffle comprises one or more throughdistribution holes.
 5. Heat exchanger as in claim 4, wherein said one ormore through distribution holes have a variable cross section withrespect to the thickness of said distributor baffle, having alongitudinal section with a conical or truncated-cone shape.
 6. Heatexchanger as in claim 1, wherein a single circulation element isdisposed between at least one of said end caps and said distributorbaffle.
 7. Heat exchanger as in claim 1, wherein said damping meanscomprise at least one phase shifter unit which comprises a phase shiftchamber configured as a tubular body and fluidically connected to atleast one manifold by means of a single pipe.
 8. Heat exchanger as inclaim 1, wherein said damping means comprise at least one phase shifterunit which comprises a phase shift chamber configured as a tubular bodyand fluidically connected to at least one manifold by means of a firstinlet pipe and a second outlet pipe.
 9. Heat exchanger as in claim 7,further comprising at least one feed pipe and at least one recoverypipe, wherein said feed pipe and said recovery pipe are fluidicallyconnected to a first manifold comprising said distributor baffle, theheat exchanger further comprises a second manifold associated with aphase shifter unit.
 10. Heat exchanger as in claim 1, wherein saidcirculation elements comprise a plurality of channels whose passagecross section is comprised between about 5*10⁻⁵ and about 20 squaremillimeters.
 11. Heat exchanger as in claim 1, wherein the damping meanscomprise one or more protrusions and/or one or more tubular elementsassociated with at least one of either: a dividing baffle disposed insaid one or more manifolds, or end caps of said one or more manifolds,or walls of said manifolds.
 12. Heat exchanger as in claim 1, whereinsaid damping means comprise a mobile damper element comprising a bodyoperatively associated with said manifold by means of elastic meansconfigured to absorb said pulsations so as to capture the pressurepulsations transmitted in the heat-carrier fluid, and/or a flexiblemembrane, operatively associated with said manifold and configured toabsorb vibrations which are transmitted in the heat-carrier fluid.